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PubMed1993

Toxic effects of linear alkylbenzene sulfonate on the tiger prawn, Penaeus monodon.

The toxic effects of linear alkybenzene sulfonate (LAS) on the larvae and juveniles of tiger prawn Penaeus monodon were tested. The 24-hr LC50 values of LAS were 0.06, 0.10, and 3.11 ppm for the zoea 2nd substage, mysis 2nd substage (M2), and postlarva 12th substage (PL12) of the tiger prawn, respectively. The 48-hr LC50 values of LAS were 0.07, 1.03, and 4.36 ppm for M2, PL12, and postlarva 15th substage of the tiger prawn, respectively. The hepatopancreatic glutathione (GSH) in juvenile tiger prawn was obviously depleted when LAS concentration was over 1.0 ppm. The hepatopancreatic GSH content of tiger prawn exposed to solutions of greater than 1.0 ppm LAS was difficult to raise to normal levels, even after the tiger prawns were switched to an LAS-free solution. The activity of malate dehydrogenase in the serum of juvenile tiger prawns exposed to 10.0 ppm LAS solution was significantly increased.

Alkanesulfonic Acids↗
PubMed2005

Novel diagnostic catheter specifically designed for both coronary arteries via the right transradial approach. A prospective, randomized trial of Tiger II vs. Judkins catheters.

The aim of this study was to assess the feasibility, safety, and performance of a novel diagnostic catheter specifically designed for engaging both coronary arteries via the right transradial artery approach. A total of 160 patients were randomized between the standard Judkins (5F R4, L4; Cordis Corporation, Miami, FL) and the 5F Tiger II (Terumo Corporation, Tokyo, Japan) catheters. End points included the duration of various procedures and the assessments of angiographic image quality and catheter performance. The Tiger II was associated with a significantly shorter (40%) total procedure time (199.6+/-50.2 vs. 331.5+/-72.9 s, p=0.001) and a 33% shorter total fluoroscopic time (93.1+/-33.8 vs. 138.2+/-47.6 s, p=0.001) for diagnostic coronary angiography, compared with those with the Judkins catheter. There was no significant difference between the Tiger II and Judkins catheters for left coronary angiographic quality (left anterior descending, 2.82+/-0.48 vs. 2.94+/-0.29, p=0.084; left circumflex, 2.90+/-0.38 vs. 2.87+/-0.44, p=0.629). The Tiger II provided superior right coronary angiograms, compared with the Judkins catheter (2.99+/- 0.11 vs. 2.82+/-0.48, p=0.003). For the left coronary angiograms, the initial randomized catheter completed the procedure in 91% of the patients with the Tiger II and in 98% with the Judkins (p=0.167) catheters. For the right coronary angiograms, 100% were completed with the Tiger II and 95% with the Judkins (p=0.120) catheters. There were no angiographic or clinical complications in either group, so the procedural success rate was 100%. The potential of the Tiger II catheter for use as a multipurpose catheter for right transradial coronary angiography to reduce procedural and X-ray times to the level of classic transfemoral coronary angiography has to be confirmed in a randomized study.

Cardiac Catheterization↗
PubMed1989

Ultrastructure of the domestic tom cat (Felis domestica ) and tiger (Panthera tigris altaica ) spermatozoa.

The ultrastructure of spermatozoa from the domestic tom cat and the Siberian tiger was studied. Semen was collected from anesthetized tom cats and Siberian tigers by electroejaculation. Spermatozoa were fixed and processed for examination by transmission electron microscopy. The principle differences between the spermatozoa from the two species were the head shape, mitochondrial organization in the neck area and structure of the fibrous sheath. Tom cat spermatozoa had an elongated oval-shaped head, while tiger spermatozoa had a more rounded head shape. Circularly oriented mitochondria in the neck area, near the proximal centriole, were frequently observed in tiger cells but rarely observed in tom cat cells. The semicircular ribs of tom cat spermatozoa were larger than the ribs of tiger spermatozoa. Also, the dense fibers (Numbers 3 and 8) of the corresponding microtubule doublets were fused or connected to the longitudinal columns in tiger spermatozoa but showed only occasional attachment in tom cat spermatozoa. These differences could influence results when the tom cat is used as a model for studying tiger semen.

Journal Article↗
PubMed2004

An application of visible human database in radiotherapy: tutorial for image guided external radiotherapy (TIGER).

BACKGROUND AND PURPOSE: Three-dimensional conformal radiotherapy and intensity modulated radiotherapy allow accurate dose delivery on target volumes. Due to the different background among specialists involved in target volume definition, the contouring emerges as one of the most questionable steps in treatment planning procedures. A software tool devoted to contouring training, named tutorial for image guided external radiotherapy ('TIGER'), based on the Visible Human Project images data-set, is described. MATERIALS AND METHODS: TIGER is addressed to facilitate the learning of axial anatomical images, to promote the training and reproducibility in contouring process, to allow the availability of a tool to enhance the 'drill and practice' approach in training programs. TIGER includes three different environments: Anatomic tutorial devoted to facilitate a self-learning approach to axial body sections; Contouring tutorial addressed to practice contouring process of anatomical structures and to undergo a test program prepared by tutors; Teacher's tools to offer to tutors the opportunity to insert new outlines in TIGER-database, according to local needs or conventions, and to use them in tutorial programs. TIGER-database is grouped in six main anatomical sections: head and neck, male thorax, female thorax, abdomen, male pelvis, and female pelvis. Overall 432 corresponding CT-VH images and 1189 contours of 134 different anatomical structures and lymphatic drainage areas are available. The access to the TIGER software is allowed by ESTRO web site (http://www.estro.be). CONCLUSIONS: TIGER provides an interactive human anatomy cross-sectional oriented source to facilitate the interpretation of CT scan images usually contoured in daily practice. It offers a drill tool to facilitate the learning of a reproducible contouring procedure.

Databases as Topic↗
PubMed1999

Phylogeographical population structure of tiger quolls Dasyurus maculatus (Dasyuridae: Marsupialia), an endangered carnivorous marsupial.

Tiger quolls, Dasyurus maculatus, are the largest carnivorous marsupials still extant on the mainland of Australia, and occupy an important ecological niche as top predators and scavengers. Two allopatric subspecies are recognized, D.m. gracilis in north Queensland, and D.m. maculatus in the southeast of the mainland and Tasmania. D.m. gracilis is considered endangered while D.m. maculatus is listed as vulnerable to extinction; both subspecies are still in decline. Phylogeographical subdivision was examined to determine evolutionarily significant units (ESUs) and management units (MUs) among populations of tiger quolls to assist in the conservation of these taxa. Ninety-three tiger quolls from nine representative populations were sampled from throughout the species range. Six nuclear microsatellite loci and the mitochondrial DNA (mtDNA) control region (471 bp) were used to examine ESUs and MUs in this species. We demonstrated that Tasmanian tiger quolls are reciprocally monophyletic to those from the mainland using mtDNA analysis, but D.m. gracilis was not monophyletic with respect to mainland D.m. maculatus. Analysis of microsatellite loci also revealed significant differences between the Tasmanian and mainland tiger quolls, and between D.m. gracilis and mainland D.m. maculatus. These results indicate that Tasmanian and mainland tiger quolls form two distinct evolutionary units but that D.m. gracilis and mainland D.m. maculatus are different MUs within the same ESU. The two marker types used in this study revealed different male and female dispersal patterns and indicate that the most appropriate units for short-term management are local populations. A revised classification and management plan are needed for tiger quolls, particularly in relation to conservation of the Tasmanian and Queensland populations.

Animals↗
PubMedDate not supplied

A tiger mouse and relatives. Variants caused by an activated transposable element?

In a laboratory-bred population of wild Peruvian house mice, one male had an excessive rate of non-pairing of the X and Y chromosomes. After crossing him with laboratory stock mice, a mouse of very unusual phenotype appeared from a yellow (AyA) mother. He was yellow with black dorsal stripes; hence Tiger. He was mated to many females, and inbred F2 and F3 generations were raised. There were no more tiger phenotypes, but his F1 contained an excess of black-and-tans over yellows, showing him to be a gonosomic mosaic Ayat/atat; the homozygous cell line probably arose from the heterozygous one. The mitotic karyotype was normal. Some of Tiger's mates were of known allozyme types and their progeny were scored. The allozyme segregations were normal, except at the Es-3 locus (esterase-3), for which Tiger was typed as homozygous. Several unusual events among Tiger's close relatives included a mutation to an unstable pattern mutant, three probable translocations, and several cases of somatic defect. All unusual mice derived from Tiger's yellow mother, whose genome was one-quarter Peruvian. Yellow is associated with an ecotropic murine leukemia virus. The Peru genome is characterized by a high occurrence of mutation and aberrant karyotypes. It is suggested that something from the Peru genome in Tiger's mother caused instability of the DNA sequence associated with yellow, with related disturbance at different locations thereafter. The nature of this instability, and of the Peru genome, is discussed.

Animals↗
PubMed1990

Comparison of serum and plasma taurine values in Bengal tigers with values in taurine-sufficient and -deficient domestic cats.

A white Bengal tiger was determined to have a central retinal lesion and a central visual defect. Because of the known association between feline central retinal degeneration (CRD) and taurine deficiency in domestic cats, plasma concentrations of taurine were measured in this tiger. Serum concentrations of taurine, methionine, and cystine also were measured in white Bengal tigers, orange Bengal tigers, taurine-sufficient domestic cats, and taurine-deprived and tissue-taurine-depleted visually impaired cats with CRD. Hepatic and brain enzymes responsible for taurine synthesis were identified in tissue specimens from an orange Bengal tiger. Serum taurine concentrations were lower in white vs orange tigers, but were not as low as those in cats with CRD. Thus, we concluded that taurine depletion did not account for the central retinal lesion in the white Bengal tiger.

Animals↗
PubMed2005

Molecular cloning and characterization of cDNA of penaeidin-like antimicrobial peptide from tiger shrimp (Penaeus monodon).

We report the molecular cloning and characterization of a penaeidin-like antimicrobial peptide (AMP) complementary DNA from the hemocytes of tiger shrimp (Penaeus monodoni). A tiger shrimp AMP cDNA containing the entire coding region of the peptide, determined by rapid amplification of cDNA 5' and 3' ends and polymerase chain reaction of the messenger RNA isolated from hemocytes of the shrimp, is 683 bp in length with an open reading frame of 222 bp. The deduced amino acid sequence of this antimicrobial peptide consists of 55 amino acid residues of the mature peptide and a signal peptide of 19 amino acid residues. The mature peptide contains a proline-rich domain at the N terminus and 6 cysteine residues at the C terminus, and it shares less than 50% amino acid sequence identity with the mature penaeidins of Litopenaeus vannamei. To demonstrate the bactericidal activity of this peptide, a synthetic peptide was prepared according to the amino acid sequence deduced from the cDNA of tiger shrimp penaeidin-like AMP. By the minimal inhibitory concentration MIC assay, the synthetic peptide was shown to exert bactericidal activity against Escherichia coli, Vibrio harveyi, Vibrio alginolyticu, and Aerococcus viridans. It also inhibited the growth of 2 filamentous fungi, Fusarium pisi and Fusarium oxysporum. Tiger shrimp penaeidin-like AMP mRNA was detected in hemocytes, gills, intestines, eyestalks, hepatopancreas, and muscles of the tiger shrimp by reverse transcriptase-polymerase chain reaction assay. Although the highest level was detected in hemocytes, challenging tiger shrimp with V. harveyi did not result in a significant increase of the mRNA level in hemocytes.

Amino Acid Sequence↗
PubMed2005

Characterization of tiger-tail banding and hair shaft abnormalities in trichothiodystrophy.

BACKGROUND: Tiger tail banding under polarizing light microscopy and hair shaft abnormalities are associated with trichothiodystrophy (TTD), a rare disorder with a wide spectrum of clinical presentations. OBJECTIVE: To characterize the frequency, specificity, and extent of tiger tail banding and hair shaft abnormalities in the spectrum of TTD patients. METHODS: We developed a standardized procedure for microscopic hair examination and studied hairs from 14 TTD and 4 xeroderma pigmentosum (XP)-TTD patients for tiger tail banding and hair shaft abnormalities. For comparison we examined hairs from 173 control donors consisting of 15 normals, 13 XP patients, 11 family members of XP or TTD patients, 101 patients with various cornification disorders, and 33 leukodystrophy patients. Amino acid analysis performed on hair from the TTD and XP-TTD patients showed low sulfur content. RESULTS: Using a rotating microscope stage, all hairs in each TTD sample showed tiger tail banding under polarized light in association with a variety of hair shaft abnormalities (trichoschisis, trichorrhexis nodosa-like defects, surface irregularities, and ribboning). None of the control hairs showed tiger tail banding, and 5 of 173 controls had weathering hair shaft abnormalities. CONCLUSIONS: In patients with clinical features suggestive of TTD, tiger tail banding seen in all hairs with polarizing microscopy, in conjunction with certain hair shaft abnormalities, provides a reliable diagnostic test.

Cystine↗
PubMed1982

Effect of a proprietary rubefacient "Tiger Balm" on rabbit skin.

The effect of continuous exposure to proprietary rubefacients (Tiger Balm Red and Tiger Balm White), which contain menthol and camphor as well as clove, cajuput and cassia oils, was tested in rabbits. Dermal irritancy was determined by a 21-day continuous-application patch test (0.5 g/patch) and was assessed according to the Draize method of scoring. At the end of the 21-day test period, the skin was also examined histopathologically. In these tests, Tiger Balm Red (which contained 5% cassia oil plus 5% clove oil) caused irritation consisting of erythema, eschar formation and some oedema, to which a degree of tolerance developed. This irritation resulted in hyperkeratosis and sometimes inflammatory changes but no major damage to the skin. Tiger Balm White (no cassia oil and 2% clove oil) was better tolerated and produced less irritation and histological change than either TIger Balm Red or a mixture of commercial waxes similar in composition to the wax base for Tiger Balm Red. None of the treatments produced any signs of systemic toxicity.

Animals↗
PubMed1985

Immunoreactive luteinizing hormone, estradiol, progesterone, testosterone, and androstenedione levels during the breeding season and anestrus in Siberian tigers.

Seasonal analysis of 1239 captive births of Siberian tigers (Panthera tigris altaica) indicated a peak in April to June (P less than 0.001). Studies on seven animals in Minnesota indicated that behavioral heat cycles and ovarian follicular phase cycles began in late January and ceased in early June. Behavioral observation of 12 heat cycles in four tigers yielded an estrous length of 5.3 +/- 0.2 days and an interestrous interval of 25.0 +/- 1.3 days. Hormone assays on weekly blood samples (N = 180) from three female tigers indicated 16 cycles in two breeding seasons. Peak estradiol-17 beta levels were 46.7 +/- 6.0 pg/ml (N = 17) and interestrous concentrations were 8.7 +/- 0.66 pg/ml (N = 28) during the breeding season. Anestrous estradiol levels were 4.2 +/- 0.5 pg/ml (N = 70). The interestrous interval between estradiol peaks was 24.9 +/- 1.3 days (N = 9) with two outliers of 42 days. Serum progesterone concentrations from February to June were 1.2 +/- 0.15 ng/ml (N = 32), providing no evidence for ovulation or corpus luteum formation. Luteinizing hormone (LH) levels were 0.56 +/- 0.04 ng/ml (N = 180). Serum testosterone (r=0.71, P less than 0.001) and androstenedione levels (r=0.75, P less than 0.001) were correlated with estradiol during the breeding season. The duration of anestrus was 8 mo in two of these tigers. The interval was shortened in one tiger by exposure to a 16L:8D photoperiod. The Siberian tiger appears to be a polyestrous seasonal breeder and an induced ovulator whose breeding season may be synchronized by photoperiod.

Androstenedione↗
PubMed2006

Tiger moth responses to a simulated bat attack: timing and duty cycle.

Many night-flying insects perform complex, aerobatic escape maneuvers when echolocating bats initiate attack. Tiger moths couple this kinematic defense with an acoustic reply to a bat's biosonar-guided assault. The jamming hypothesis for the function of these moth sounds assumes that tiger moth clicks presented at high densities, temporally locked to the terminal phase of the bat attack will produce the greatest jamming efficacy. Concomitantly, this hypothesis argues that moths warning bats of bad tasting chemicals sequestered in their tissues should call early to give the bat time to process the meaning of the warning signal and that moths calling at low duty cycles are more likely to employ such an aposematic strategy. We report here the first investigation of a tiger moth assemblage's response to playback of a bat echolocation attack sequence. This assemblage of arctiid moths first answered the echolocation attack sequence 960+/-547 ms (mean +/- s.d.) from the end of the bat attack. The assemblage reached a half-maximum response shortly after the first response, at 763+/-479 ms from the end of the terminal buzz. Tiger moth response reached a maximum at 475+/-344 ms from the end of the sequence; during the approach phase, well before the onset of the terminal buzz. In short, much of tiger moth response to bat attack occurs outside of the jamming hypotheses' predictions. Furthermore, no relationship exists between the duty cycle of a tiger moth's call (and thus the call's probability of jamming the bat) and its temporal response to bat attack. These data call into doubt the assumptions behind the jamming hypothesis as currently stated but do not directly test the functionality of arctiid sounds in disrupting echolocation in bat-moth aerial battles.

Animals↗
PubMed1992

Ability of thawed tiger (Panthera tigris) spermatozoa to fertilize conspecific eggs and bind and penetrate domestic cat eggs in vitro.

Electroejaculates from tigers were collected and half was used fresh to inseminate tiger eggs in vitro and domestic cat eggs stored in a hypertonic salt solution. The remainder was pelleted, frozen in a solution of 20% egg yolk, 11% lactose and 4% glycerol, thawed and cultured with tiger and domestic cat eggs. The motility index ((sperm % motility)+(status rating x 20))/2 for thawed spermatozoa was about 86% of that in fresh aliquots. Of the 49 tiger oocytes inseminated in vitro with fresh spermatozoa, 34 (69.4%) cleaved, compared with 33 of 47 oocytes (70.2%) cultured with thawed spermatozoa (P > 0.05). Embryos generated by either sperm treatment could develop in vitro to the 16-cell or morula stage. Fresh and thawed tiger spermatozoa were equally capable (P > 0.05) of binding and penetrating the outer and inner zona pellucida of domestic cat eggs. These results demonstrate the ability of frozen-thawed tiger spermatozoa to (i) penetrate homologous and heterologous eggs and (ii) result in conspecific, advanced development of preimplantation embryos in vitro.

Animals↗
PubMed2005

Genetic characterization of H5N1 influenza A viruses isolated from zoo tigers in Thailand.

The H5N1 avian influenza virus outbreak among zoo tigers in mid-October 2004, with 45 animals dead, indicated that the avian influenza virus could cause lethal infection in a large mammalian species apart from humans. In this outbreak investigation, six H5N1 isolates were identified and two isolates (A/Tiger/Thailand/CU-T3/04 and A/Tiger/Thailand/CU-T7/04) were selected for whole genome analysis. Phylogenetic analysis of the 8 gene segments showed that the viruses clustered within the lineage of H5N1 avian isolates from Thailand and Vietnam. The hemagglutinin (HA) gene of the viruses displayed polybasic amino acids at the cleavage site, identical to those of the 2004 H5N1 isolates, which by definition are highly pathogenic avian influenza (HPAI). In addition, sequence analyses revealed that the viruses isolated from tigers harbored few genetic changes compared with the viruses having infected chicken, humans, tigers and a leopard isolated from the early 2004 H5N1 outbreaks. Sequence analyses also showed that the tiger H5N1 isolated in October 2004 was more closely related to the chicken H5N1 isolated in July than that from January. Interestingly, all the 6 tiger H5N1 isolates contained a lysine substitution at position 627 of the PB2 protein similar to the human, but distinct from the original avian isolates.

Amino Acid Sequence↗
PubMed2006

Cloning, characterization and tissue specific expression of Amur tiger (Panthera tigris altaica) IGF-I.

Insulin-like growth factor I (IGF-I) plays an important role in regulating gonad function, which is essential for normal reproduction in animals, especially in sexual receptivity and reproductive behavior. In this study, a cDNA encoding Amur tiger (Panthera tigris altaica) IGF-I was isolated from liver total RNA using RT-PCR. The IGF-I cDNA of Amur tiger (ATIGF-I) was highly homologous to that of other animals, 84.8% to rat, 93.7% to human and horse. Alignment analysis showed that the cysteine residues and many amino acid residues of putative mature ATIGF-I are highly conserved in mammalian species, confirming the high sequence homology observed in other species. DNA encoding the mature ATIGF-I peptide was ligated with pET-DsbA expression vector and highly expressed in Escherichia coli BL21 with IPTG induction. The recombinant proteins expressed existed mostly in the soluble protein fraction, and were purified with metal affinity resins. Western blotting confirmed that the recombinant proteins reacted with antibodies against IGF-I. The results obtained here should be useful for large-scale production of biological active ATIGF-I protein, as well as for further research on growth, development, and reproduction in the Amur tiger. Tissue specific expression of ATIGF-I mRNA in the Amur tiger was examined by reverse transcription-polymerase chain reaction (RT-PCR), The major ATIGF-I mRNA expression tissue was the liver, while medium signals were found in the uterus, ovary, and pituitary, and minor signals were detected in various tissues including the heart, spleen, pancreas, and kidney. The results indicate that IGF-I might play an important role in the reproductive system and in cub development in the Amur tiger.

Amino Acid Sequence↗
PubMed2005

Molecular characterization of major histocompatibility complex class II alleles in wild tiger salamanders (Ambystoma tigrinum).

Major histocompatibility complex (MHC) class II genes are usually among the most polymorphic in vertebrate genomes because of their critical role (antigen presentation) in immune response. Prior to this study, the MHC was poorly characterized in tiger salamanders (Ambystoma tigrinum), but the congeneric axolotl (Ambystoma mexicanum) is thought to have an unusual MHC. Most notably, axolotl class II genes lack allelic variation and possess a splice variant without a full peptide binding region (PBR). The axolotl is considered immunodeficient, but it is unclear how or to what extent MHC genetics and immunodeficiency are interrelated. To study the evolution of MHC genes in urodele amphibians, we describe for the first time an expressed polymorphic class II gene in wild tiger salamanders. We sequenced the PBR of a class II gene from wild A. tigrinum (n=33) and identified nine distinct alleles. Observed heterozygosity was 73%, and there were a total of 46 polymorphic sites, most of which correspond to amino acid positions that bind peptides. Patterns of nucleotide substitutions exhibit the signature of diversifying selection, but no recombination was detected. Not surprisingly, trans-species evolution of tiger salamander and axolotl class II alleles was apparent. We have no direct data on the immunodeficiency of tiger salamanders, but the levels of polymorphism in our study population should suffice to bind a variety of foreign peptides (unlike axolotls). Our tiger salamander data suggest that the monomorphism and immunodeficiencies associated with axolotl class II genes is a relic of their unique historical demography, not their phylogenetic legacy.

Alleles↗
PubMed2003

Mucus pH of the tiger puffer Takifugu rubripes is an important factor for host identification by the monogenean Heterobothrium okamotoi.

We examined a host-finding factor of the monogenean Heterobothrium okamotoi oncomiracidia to develop an alternative prophylaxis. H. okamotoi oncomiracidia attached preferentially to gill filaments and skin mucus from the tiger puffer Takifugu rubripes compared with corresponding material from other tested fishes (amber jack Seriola dumerili, red sea bream Pagrus major, Japanese flounder Paralichthys olivaceus and spotted halibut Verasper variegatus). The body mucus pH of the tiger puffer was 6.40 +/- 0.09 (mean +/- S.D.), whereas that for the other tested fishes was 7.2-7.4. To find if this difference in pH could account for the specific targeting of tiger puffer by H. okamotoi oncomiracidia, the attachment response of the oncomiracidia to pieces of agar buffered at various pH between 6.0 and 7.4 was examined. The number of attaching oncomiracidia was maximal at pH 6.4. We produced gynogenetic tiger puffers from a single female. These gynogenetic individuals showed a variety of body mucus pH and they were exposed to the oncomiracidia. Thirteen days after exposure, more young H. okamotoi were found on the gills of gynogenetic tiger puffer with mucus at pH 6.3-6.6, than on gills of fish with mucus at pH 6.0-6.3 and 6.6-7.2. H. okamotoi exploits the body mucus pH to identify the host. The simplicity of pH as a lure may lead to development of a simple and economical method to control H. okamotoi outbreaks.

Animals↗
PubMed2004

Tigers and their prey: Predicting carnivore densities from prey abundance.

The goal of ecology is to understand interactions that determine the distribution and abundance of organisms. In principle, ecologists should be able to identify a small number of limiting resources for a species of interest, estimate densities of these resources at different locations across the landscape, and then use these estimates to predict the density of the focal species at these locations. In practice, however, development of functional relationships between abundances of species and their resources has proven extremely difficult, and examples of such predictive ability are very rare. Ecological studies of prey requirements of tigers Panthera tigris led us to develop a simple mechanistic model for predicting tiger density as a function of prey density. We tested our model using data from a landscape-scale long-term (1995-2003) field study that estimated tiger and prey densities in 11 ecologically diverse sites across India. We used field techniques and analytical methods that specifically addressed sampling and detectability, two issues that frequently present problems in macroecological studies of animal populations. Estimated densities of ungulate prey ranged between 5.3 and 63.8 animals per km2. Estimated tiger densities (3.2-16.8 tigers per 100 km2) were reasonably consistent with model predictions. The results provide evidence of a functional relationship between abundances of large carnivores and their prey under a wide range of ecological conditions. In addition to generating important insights into carnivore ecology and conservation, the study provides a potentially useful model for the rigorous conduct of macroecological science.

Animals↗